Project description:The presence of diffuse anaplasia in Wilms tumours (DAWT) is associated with TP53 mutations and poor outcome. As patients receive intensified treatment, we sought to identify whether TP53 mutational status confers additional prognostic information. We studied 40 patients with DAWT with anaplasia in the tissue from which DNA was extracted and analysed for TP53 mutations and 17p loss. The majority of cases were profiled by copy number (n=32) and gene expression (n=36) arrays. TP53 mutational status was correlated with patient event-free and overall survival, genomic copy number instability and gene expression profiling. From the 40 cases, 22 (55%) had TP53 mutations (2 detected only after deep-sequencing), 20 of which also had 17p loss (91%); 18 (45%) cases had no detectable mutation but three had 17p loss. Tumours with TP53 mutations and/or 17p loss (n=25) had an increased risk of recurrence as a first event (p=0.03, hazard ratio (HR), 3.89; 95% confidence interval (CI), 1.26-16.0) and death (p=0.04, HR, 4.95; 95% CI, 1.36-31.7) compared to tumours lacking TP53 abnormalities. DAWT carrying TP53 mutations showed increased copy number alterations compared to those with wild-type, suggesting a more unstable genome (p=0.03). These tumours showed deregulation of genes associated with cell cycle and DNA repair biological processes. This study provides evidence that TP53 mutational analysis improves risk stratification in DAWT. This requires validation in an independent cohort before clinical use as a biomarker. 36 tumour samples were expression profiled in 2-colour hybridisations with Stratagene Universal Human Reference RNA in the reference channel. There were no replicates.
Project description:The presence of diffuse anaplasia in Wilms tumours (DAWT) is associated with TP53 mutations and poor outcome. As patients receive intensified treatment, we sought to identify whether TP53 mutational status confers additional prognostic information. We studied 40 patients with DAWT with anaplasia in the tissue from which DNA was extracted and analysed for TP53 mutations and 17p loss. The majority of cases were profiled by copy number (n=32) and gene expression (n=36) arrays. TP53 mutational status was correlated with patient event-free and overall survival, genomic copy number instability and gene expression profiling. From the 40 cases, 22 (55%) had TP53 mutations (2 detected only after deep-sequencing), 20 of which also had 17p loss (91%); 18 (45%) cases had no detectable mutation but three had 17p loss. Tumours with TP53 mutations and/or 17p loss (n=25) had an increased risk of recurrence as a first event (p=0.03, hazard ratio (HR), 3.89; 95% confidence interval (CI), 1.26-16.0) and death (p=0.04, HR, 4.95; 95% CI, 1.36-31.7) compared to tumours lacking TP53 abnormalities. DAWT carrying TP53 mutations showed increased copy number alterations compared to those with wild-type, suggesting a more unstable genome (p=0.03). These tumours showed deregulation of genes associated with cell cycle and DNA repair biological processes. This study provides evidence that TP53 mutational analysis improves risk stratification in DAWT. This requires validation in an independent cohort before clinical use as a biomarker. 32 tumour samples were profiled by aCGH, in 2-colour hybridisations with common pooled unrelated normal genomic DNA in the reference channel. There were no replicates.
Project description:We have carried out microarray-based comparative genomic hybridisation (arrayCGH) on 17 Favourable histology Wilms tumour samples taken at immediate nephrectomy in order to identify changes in DNA copy number associated with clinical outcome. Tumour DNA was co-hybridised with normal female genomic DNA onto microarrays consisting of 2118 BAC clones with tiling-path coverage of chromosome 1. Data was normalised and quality-filtered, an adapted weights smoothing algorithm fitted, and changes in DNA copy number assessed for each clone.
Project description:Gene expression profiles in 15 day old low oil 1 (loo1) mutant and the wild type A15 seedlings were compared. Keywords: Comparison and loo1 and wild type seedling transcriptomes The loo1 mutant and the wild type seedlings transcriptomes were compared using 70-mer oligoarrays. Two experimental repeats were conducted, each with two dye-swap hybridizations.
Project description:We have carried out microarray-based comparative genomic hybridisation (arrayCGH) on 100 favourable histology Wilms tumour samples taken at immediate nephrectomy in order to identify changes in DNA copy number associated with clinical outcome. Tumour DNA was co-hybridised with normal female genomic DNA onto microarrays consisting of 4263 BAC clones with an approximate 1Mb spacing throughout the genome. Data was normalised and quality-filtered, an adapted weights smoothing algorithm fitted, and changes in DNA copy number assessed for each clone.
Project description:The type III effector (T3E) AWR5 from the phytopathogen Ralstonia solanacearum causes disease in many plants relevant in agriculture. Heterologous expression in yeast of AWR5 from an integrated tetO promoter caused strong growth inhibition. In this series of experiments we investigate the possible changes in the transcriptional profile in a time-course (2, 4 and 6 h) response to AWR5 production. Yeast strains were grown overnight in rich YPD medium with doxycycline 15 µg/ml (repressing conditions), then normalized to OD600=0.05 and grown resumed in YPD+dox (non-inducing conditions) or YPD (inducing conditions). Samples were taken at 2, 4 or 6 hours for each condition. Two biological replicates were made for each time point.
Project description:Understanding the genetic architecture of cancer pathways that distinguishes subsets of human cancer is critical to developing new therapies that better target tumors based upon their molecular expression profiles. In this study, we identify an integrated gene signature from multiple transgenic models of epithelial cancers intrinsic to the functions of the Simean virus 40 T/t-antigens that is associated with the biologic behavior and prognosis for several human epithelial tumors. This genetic signature, composed primarily of genes regulating cell replication, proliferation, DNA repair and apoptosis, is not a general cancer signature. Rather, it is uniquely activated primarily in tumors with aberrant p53, Rb or BRCA1 expression, but not in tumors initiated through the overexpression of myc, ras, her2/neu, or Polyoma middle T oncogenes. Importantly, human breast, lung and prostate tumors expressing this set of genes represent subsets of tumors with the most aggressive phenotype and with poor prognosis. The T/t-antigen signature is highly predictive of human breast cancer prognosis. Since this class of epithelial tumors is generally intractable to currently existing standard therapies, this genetic signature identifies potential targets for novel therapies directed against these lethal forms of cancer. Since the these genetic targets have been discovered using mammary, prostate, and lung T/t-antigen mouse cancer models, these models are rationale candidates for use in pre-clinical testing of therapies focused on these biologically important targets. Keywords: SuperSeries Gene expression profiles from the SV40 T/t-antigen mouse models were compared with respect to specimen type (normal vs. tumor tissue), location of tumor (mammary, lung, prostate, seminal vesicle), and background strain of mice (FVB vs. C57BL/6). A three-way ANOVA model with one interaction effect (type X location) was fitted. Cancer genes that differ among all four tumor locations were identified, as those that had a significant interaction effect at the 0.001 level and showed at least a 2-fold change between the maximal and minimal mean tumor/normal ratio over the different locations (2638 cDNA probes). Based on the ANOVA model, differentially expressed genes between normal and tumor specimens within each tumor location were also identified, as those genes whose expression were significant at the 0.001 level and were at least 2-fold different compared to the mean expression ratio. Overall 3004 unique array features were selected using ANOVA. Further selection was applied based upon identification of differentially expressed genes between normal and tumor tissue for the three epithelial tumors (mammary, lung and prostate). The SV40 T/t-antigen oncogene-specific signature included genes similarly differentially expressed in each epithelial tumor (153 cDNA clones). In contrast, genes were included in a tissue-specific SV40 T/t-antigen tumor signature if they were found to be differentially expressed between the tumor and normal samples exclusively for one location. Two-hundred and eighty three, 220 and 999 cDNA clones were identified as specifically dysregulated in mammary, lung and prostate tumors, respectively).
Project description:Understanding the genetic architecture of cancer pathways that distinguishes subsets of human cancer is critical to developing new therapies that better target tumors based upon their molecular expression profiles. In this study, we identify an integrated gene signature from multiple transgenic models of epithelial cancers intrinsic to the functions of the Simean virus 40 T/t-antigens that is associated with the biologic behavior and prognosis for several human epithelial tumors. This genetic signature, composed primarily of genes regulating cell replication, proliferation, DNA repair and apoptosis, is not a general cancer signature. Rather, it is uniquely activated primarily in tumors with aberrant p53, Rb or BRCA1 expression, but not in tumors initiated through the overexpression of myc, ras, her2/neu, or Polyoma middle T oncogenes. Importantly, human breast, lung and prostate tumors expressing this set of genes represent subsets of tumors with the most aggressive phenotype and with poor prognosis. The T/t-antigen signature is highly predictive of human breast cancer prognosis. Since this class of epithelial tumors is generally intractable to currently existing standard therapies, this genetic signature identifies potential targets for novel therapies directed against these lethal forms of cancer. Since the these genetic targets have been discovered using mammary, prostate, and lung T/t-antigen mouse cancer models, these models are rationale candidates for use in pre-clinical testing of therapies focused on these biologically important targets. Keywords: Genetically engineered mouse (GEM) models of cancer, epithelial carcinoma, SV40 T/t-antigen, survival predictor Gene expression profiles from the SV40 T/t-antigen mouse models were compared with respect to specimen type (normal vs. tumor tissue), location of tumor (mammary, lung, prostate, seminal vesicle), and background strain of mice (FVB vs. C57BL/6). A three-way ANOVA model with one interaction effect (type X location) was fitted. Cancer genes that differ among all four tumor locations were identified, as those that had a significant interaction effect at the 0.001 level and showed at least a 2-fold change between the maximal and minimal mean tumor/normal ratio over the different locations (2638 cDNA probes). Based on the ANOVA model, differentially expressed genes between normal and tumor specimens within each tumor location were also identified, as those genes whose expression were significant at the 0.001 level and were at least 2-fold different compared to the mean expression ratio. Overall 3004 unique array features were selected using ANOVA. Further selection was applied based upon identification of differentially expressed genes between normal and tumor tissue for the three epithelial tumors (mammary, lung and prostate). The SV40 T/t-antigen oncogene-specific signature included genes similarly differentially expressed in each epithelial tumor (153 cDNA clones). In contrast, genes were included in a tissue-specific SV40 T/t-antigen tumor signature if they were found to be differentially expressed between the tumor and normal samples exclusively for one location. Two-hundred and eighty three, 220 and 999 cDNA clones were identified as specifically dysregulated in mammary, lung and prostate tumors, respectively). This set of the mammary mouse tumor models was used to demonstrate that the intrinsic SV40 T/t-antigen signature is not a feature of tumors initiated by other oncogenes or inactivation of supressor genes, but is most specific to tumors induced by T/t-antigen.
Project description:Understanding the genetic architecture of cancer pathways that distinguishes subsets of human cancer is critical to developing new therapies that better target tumors based upon their molecular expression profiles. In this study, we identify an integrated gene signature from multiple transgenic models of epithelial cancers intrinsic to the functions of the Simean virus 40 T/t-antigens that is associated with the biologic behavior and prognosis for several human epithelial tumors. This genetic signature, composed primarily of genes regulating cell replication, proliferation, DNA repair and apoptosis, is not a general cancer signature. Rather, it is uniquely activated primarily in tumors with aberrant p53, Rb or BRCA1 expression, but not in tumors initiated through the overexpression of myc, ras, her2/neu, or Polyoma middle T oncogenes. Importantly, human breast, lung and prostate tumors expressing this set of genes represent subsets of tumors with the most aggressive phenotype and with poor prognosis. The T/t-antigen signature is highly predictive of human breast cancer prognosis. Since this class of epithelial tumors is generally intractable to currently existing standard therapies, this genetic signature identifies potential targets for novel therapies directed against these lethal forms of cancer. Since the these genetic targets have been discovered using mammary, prostate, and lung T/t-antigen mouse cancer models, these models are rationale candidates for use in pre-clinical testing of therapies focused on these biologically important targets. Keywords: Genetically engineered mouse (GEM) models of cancer, epithelial carcinoma, SV40 T/t-antigen, survival predictor Gene expression profiles from the SV40 T/t-antigen mouse models were compared with respect to specimen type (normal vs. tumor tissue), location of tumor (mammary, lung, prostate, seminal vesicle), and background strain of mice (FVB vs. C57BL/6). A three-way ANOVA model with one interaction effect (type X location) was fitted. Cancer genes that differ among all four tumor locations were identified, as those that had a significant interaction effect at the 0.001 level and showed at least a 2-fold change between the maximal and minimal mean tumor/normal ratio over the different locations (2638 cDNA probes). Based on the ANOVA model, differentially expressed genes between normal and tumor specimens within each tumor location were also identified, as those genes whose expression were significant at the 0.001 level and were at least 2-fold different compared to the mean expression ratio. Overall 3004 unique array features were selected using ANOVA. Further selection was applied based upon identification of differentially expressed genes between normal and tumor tissue for the three epithelial tumors (mammary, lung and prostate). The SV40 T/t-antigen oncogene-specific signature included genes similarly differentially expressed in each epithelial tumor (153 cDNA clones). In contrast, genes were included in a tissue-specific SV40 T/t-antigen tumor signature if they were found to be differentially expressed between the tumor and normal samples exclusively for one location. Two-hundred and eighty three, 220 and 999 cDNA clones were identified as specifically dysregulated in mammary, lung and prostate tumors, respectively).
Project description:Transcriptional profiling of M. smegmatis JR121 expressing VapC and VapBC grown in flasks on Hartmans de Bont medium supplemented with 0.2% glycerol Comparing transcriptional response of strain JR121 to conditional expression of VapC toxin compared with the expression of VapBC complex. Biological replicates: 4 independently grown and harvested. One replicate per array.